Boring bar



v ing portionsii; said bearing: portions being 55 Patented Oct. 4, 1927.

earl-"eo- J 'HN'Mi M R Y, JR,- oF'oLEvELANn, OHIO, Assie'iion'ftiio am mammmcom PANY; OF'CLEVELAND, OHIO, Aj ooRPonMIoNoro HIo.

BORING BAR.

Application filed May 10, 1922. Serial No. 559,918.

adjustment can be had;

Another objectof the'invention is to providea block adapted tobeplaced in a line bar and carrying means i'or adjusting theblades; and means for accurately locating this: block so that the blades can be accurately adjusted with reference tothecenter of the line bar; I

Another object ofthe; invention is to provid'ano'vel construction'of pilot strips used in connection with thebear-ing'portionsof the lineloafi With these various objects in View the invention" consists in the novel features of construction and in combining or arranging the saine; all of which will' be described here= inafter and setforth in the appended-claims.

In the drawings forming a part of this specification, Fig; 1 is-"a sectional View showing a portion of bar with ablock arranged therein, said -block heing'provided with blades and-means for adjusting saidl blades; and this-view also discloses thenovel means "for" locating the block with-in the bar; Fig. 2 is a side elevation of the bar showingthe bloclr arranged t-herein and' bladescarrie'd tlrereby; Eig: Sis'a sideview of aFlin'e ba-r1 with bearing portions and I the" cutting bla'des arranged in the slot in'the line baritogeth 'er with means for adjusting the saine; Fig-. 4 is an enlarged sectional View on'the' line' Haof Figi 5'is adetailseC- tional view on the line 5 5 o'f'F-ig; 4; Fig. 6 isr-a detail section on=tlie line 6"6 of Fig. 4; is a detail sectional view on' 'the" lin'e 7-7 of Fig; 3; and :'F ig; 81s a sectional viewon the line8'8 oi-Fig. 1. v v

Incarrying out niy invention I employ a" rotary-stock or line bar 10 having the bearprov'ided with pilot strips 1-2 constructed and arranged in a mannermore clearly describedhereinafter;

Therotary stock or line bar lt) has one inoie transverse slot-s therethrou-gh in" order to receive" the cutting blades 1-3 findparts:

connected therewith, the outer en'ds of aud t bla-des being: shaped according tothe-"pus; poses for w'h'ieli they are intended:

If have devised'a novelferm efm'enns: fi' ad usting the blades in ardent as d' jredg.

andthis novel means for adjusti g; th blades can be employed when the bladesfiai' arranged directly in the transversesjl'e't in the line bar or stock; andwhen' the ciitti' blades are ad-j'u'stably arranged-in a bloc also provide a novel form ofdevice-"fo'r properly locating'the block within the line bar or stock.

As all of the feature's' employedin con nection' with the blades carried by th'e-block are to'be'i ound in the constructionherein the, blades are arranged in the slot' in the 1ny' invention which includes tlie bleak-1&

whichis' arranged in the transverse slotcut in the line bar or rotary stock 10,

The-block 14- is of a width to-"snegly' fit the' opening 10 as'mosecleany shown, but" is of less length than i said" opening as r'no's'tclearly show'n' in'Figs. 1- ands, and -in o'rdei to lock the block in sition-1 emplo a wed-ge keylo having its flat face contaj'cting with the end of the block, and} its wedge? faces 15 engagedby the Wedge exiterfsions 16;" or the nuts lta which engage the 'opfio sit'ely threaded ends o'f thedouble serew lT, held in a centralbeari'ng portiei'i' 18 left at the neuteroi 'the st ockoi" b as street fleas-1y;

shown in Fig. l, the nuts traveling forth upon the oppositely tl ireadedfport'ions 7 of the screw'll", each end o't the" screw hav mg a socket 17 into whiclraf-wrench can-be fittedandit will'be noted by reference-t6 Fig. 2that the end-ofthe transversefopenin'g' is shapedtofreceive the nuts 16; andtheirwedgeex-tensions 16?; v

The opposite end of tlre block l li -hasaf at this endo'ffth'e transverse slotf10' thestock is als'o provided-'witha recess 20in which is" arranged a meeting keyor nut 21 noted that th'ere'is someclarance betweenfthe key and end of the block inorder taper mit the key 21 to be first introduced and then the block 14 inserted, it being understood, that the wedge locking means applied to the key 15 are released in order to give ample space for the insertion oi? the block 14.

The stock or bar 10 is also bored transversely as shown at 10 and one end of this bore is threaded as shown at 22 while the opposite end is smooth as shown at 23, and threaded into the key 21 is a screw 24 which screw has an enlarged portion, threaded to engage the threads 22 of bore 10 and it will be noted that the threads 24 are much finer than the threads 25 and consequently when the differential screw is turned in one direction the locating key 21 will be moved a distance equal to the difference between the pitch of the coarse thread and the pitch of the fine thread and in this way exceedingly fine and easy adjustment of the locating key 21, and. consequently oi the block 14 is obtained.

A threaded bushing 26 is screwed upon the projecting reduced portion of the differential screw after the locating key has been Y of cutting tools and their carrying parts has been more or less difficult, but by means of the differential screw and locating key here-- in shown and described I am able to obtain exceedingly fine and accurate adjustments as" it is obvious that by making the two pitches of the screws nearly equal, that a single turn of the screw must necessarily move the key only an exceedingly short distance, inasmuch as such distancecan only be the difference between the two pitches ot the screw.

The block 14 is transversely slotted as shown at 14 to receive the blades 13, and at each end, communicating with the slot 14 in which the blades move, are the keyhole extensions 14 and 14, which communicate with the slot 14" and each portion 14 and 14 has a central bearing portion 30, and in the extension 14 is mounted the double reversely threaded screw 31 which actuates the nuts 32, each provided with a lug 33 which engage a recess 34 produced in the adjacent edge of the blade 13, there being clearance between the end of lug and wall of recess as shown so that the blades can be inserted after the locking means have been released as hereafter explained.

The ends of the double screw 31are journaled in side plates 35, set in the sides or" the block and the square ends of the plates are fiush with the end of the transverse slot 10,

and it will be noted that the edges of the blades contact with the end of the slot (see Fig. 8) and also with the straight edges of the plates.

The screw 31 has a socket 31 at each end into which a wrench can be fitted to turn the double screw, and it is obvious that when the double screw is turned in either direction the 4 nuts 32 will be moved in unison in opposite directions and their lugs 33 being in engagement with the blades will cause said blades to move in or out in unison.

By having the blades slide in the slot and.

having the nuts working on the double screw,

these screws can be cut with comparatively fine threads and in this way fine adjustments can be had.

After the blades have been thus adjusted in the block I lock them in their adjusted positions by means of a wedge key 36 which tits in the extension 14 and bears with its fiat face upon the edges of theblade, and the wedge faces 36* are engaged by the wedge lugs 37 of the nuts 37 working on the double reversely threaded screw 38 journaled in the bearing 18 projecting into the slot extension The screw 38 has sockets 38, at the ends 14 to receive a wrench. The screw 38 is turned to release the lock whenever it is desired to adjust the blades, and tightened after the adjustment is obtained.

The adjustment of the blades is had by turning the screw 31 in the proper direction and by placing graduations upon the plate 85, and a point upon the end of the screw, the exact amount of movement of the blades can be determined.

The block 14 is located by means of the lllf) location key or nut 21 actuated by the differential screw 24-25 as previously described, and by having this double adjustment I am able to properly and accurately adjust the blades with reference to the true center of the line bar so that an accurate hole willbe cut.

In the construction shown in Figs. 8, 4 and 5 the slot 10 is cut in the bar and is. provided with extension 10 and 10 the double reversely threaded screw 40 being arranged in the extension 10 and the double screw 41 in the extension 10*.

On the screw 40 are the nuts 42 having lugs 43 which fit int-o recess 44 in the blades 13 and by turning the the end of the slot 10 and as previously stated the nuts turning on the double screw and provided with lugs which engage the blades, a fine thread can be out upon the screw and fine adjustmentshad.

A wedge key 46 contacts with the opposite side of the blades and nuts 47 working on the screw 41 having wedge extensions 47* which engage the top end portion 46* of the wedge key 46 and lock the blades in the adjusted posit-ions.

The manner or adjusting the blades and the advantages of the various features have already been described in connection with Figs. 1 and 2.

In Figs. 3 and 7 I have shown a line bar 10 having bearing portions 11 provided with pilot strips 12. These strips are fastened in grooves 50 by screws 51, and after being fitted are hardened and attached, and finished off to fit the bearing. As commonly constructed they frequently break on a line with the head screw, and in order to avoid this'I provide a composite strip composed of a low carbon steel part 52, and a high carbon steel part 53 welded together at 54, so that the outer part can be hardened without aifecting the inner part, and when it becomes necessary to insert shims and regrind the outer part it can be done much more conveniently and with better results than with the strips heretofore employed,

and all danger of breakage is avoided.

From the foregoing description it will be seen that I provide a novel form of blade adjusting means, which can be-used either in a bar, or in a block within the bar, and that I also provide a novel locating means for the block when so used 'so that absolute accuracy is obtained.

Having thus described my invention, what I claim is: V

1. The combination with a slotted bar, of a block arranged therein having a recess atone end, a locating key nut arrangedin the bar and engaging the recess in the block, a differential screw, and bushing arranged in the bar, the coarse threaded portion of screw engaging the bar and the fine threaded part thereof engaging the locating key nut and bushing, means for locking said block, and blades carried by said block.

2. The combination with a member transversely slotted and transversely bored, the said bore and slotcommunicating, of a block arranged in said slot a locating key nutarranged in the member and having Vengagement with the block, a differential screw engaging the member and locating key nut, and means for protecting the ends of said screw.

In testimony whereof, I hereunto afiix my signature.

" JOHN M. MARTY, JR. 

